Resolved | May 12, 2021 | 13:45 GMT+02:00
We've heard from Microsoft's end that they should be clearing out the quarantine and routing emails appropriately.
However, there have been reports that emails still aren't being released. Businesses that use Outlook to manage their email domains have noted that they have had to manually release emails from quarantine on their own: https://twitter.com/MSFT365Status/status/1391885462722121732
Unfortunately, we're not able to force these emails to be released from quarantine since this is happening inside of Outlook. Additionally, we're still seeing seeing reports from other users of ours who have attempted resends that are still arriving in the quarantine. You may want to test this on your end to see if you're able to get around it at this point. We aren't seeing anything consistent in the feedback we've received on this issue so we can't really advise if this is the best path forward.
At this point, your best option may be to send out an email to the affected subscribers with all tracking removed (use your own mail server instead) that makes note of this issue with Outlook and the SafeLinks functionality. Your clients have the option of manually releasing emails from quarantine or disabling the SafeLinks functionality entirely while Microsoft continues to address this issue.
Inside of Transactional itself, future emails to Outlook recipients may need to have all tracking and hyperlinks removed in order to ensure delivery, at least until this issue is resolved on Microsoft's end.
We do apologize for the inconvenience here but I'm afraid that there's nothing we can do from our end since this issues is fully within Microsoft's domain. We'll continue to monitor for updates but, as before, I'm afraid we're not able to see what exactly is happening and why due to this issue existing outside of us.
Open | May 10, 2021 | 12:00 GMT+02:00
We've recently noticed an issue with Microsoft Outlook's new feature targeting some Transactional email IPs leading to delivery issues. The team of our email providing is still investigating and working with Microsoft to resolve the issue, but it appears to be related to several incidents that Microsoft is having with their Microsoft Defender service.
Specifically, the SafeLinks feature is responsible for marking URLs as suspicious, and some emails are not delivering due to safelist/blocklist expirations on their side. This is affecting other Email Service Providers.
The developers are aware of this issue and are prioritizing a fix for this by working with Microsoft developers.
Bit more in Microsoft's feature here: https://docs.microsoft.com/en-us/microsoft-365/security/office-365-security/report-junk-email-messages-to-microsoft?view=o365-worldwide
And it looks like Microsoft is aware of this issue too: https://twitter.com/MSFT365Status/status/1391805371824607235
Unfortunately we are not able to provide much in the way of a timeline for resolution since ultimately that will depend on how this issue will be handled by Microsoft (and how/when they release emails from their quarantine) but engineers and delivery folks are definitely prioritizing this issue on our end.